Phenoxy pyridines as herbicides



United States Patent 3,429,689 PHENOXY PYRIDINES AS HERBICIDES Dieter Duerr, Basel, Otto Rolir, Neuallschwil, Hans Aebi,

Riehen, and Ludwig Ebner, Stein, Aakgan, Switzerland,

assignors to Ciba Limited, Basel, Switzerland, a company of Switzerland No Drawing. Filed Jan. 27, 1965, Ser. No. 428,536 Claims priority, application Switzerland, Feb. 10, 1964,

1,532/64 U.S. C]. 71-94 5 Claims Int. 01. A0111 5/00; C07d 31/32 ABSTRACT OF THE DISCLOSURE Compounds of the general formula in which R is an aromatic radical which may be substituted by one or more halogen atoms, a lower alkyl or alkoxy radical or one of the groups NO ,OH,--CF

(in which A and A be identical or different and each is a hydrogen atom or a lower alkyl group) or the N-oxides or salts of these compounds with acids, are biocidally active and, together with a suitable carrier, provide pesticidal preparations, particularly valuable for combating insects, acarides, nematodes and micro-organisms and in the control of plant growth.

The present invention provides preparations for combating pests, more especially harmful insects, acarides, nematodes and micro-organisms, and for controlling undesired plant growth, which preparations comprise as active substance a compound of the general formula in which R represents an aromatic radical which may be substituted by one or more halogen atoms, a lower alkyl or alkoxy radical or one of the groups NO- OH, CF -CN or (in which A and A may be identical or difierent and each represents a hydrogen atom or a lower alkyl group) or comprise the Noxides or salts of these compounds with acids, together with a suitable carrier.

If desired, there may also be present one or more of the following additives: a vehicle, a solvent, a diluent, a dispersant, a wetting agent, an adhesive, a fertilizer and other pesticides.

The present invention is especially concerned with those preparations of the kind mentioned above which comprise, as active substance, a compound of the general formula 3,429,689 Patented Feb. 25, 1969 and Y represents a hydrogen atom or a chlorine atom, and 11:1, 2, 3 or 4, or those which contain as active substance a compound of the general formula (III) in which X and Y are identical or different and each represents a hydrogen atom or a chlorine atom, or a lower alkyl group containing 1 to 4 carbon atoms, or the group CF3, OI Noz.

By virtue of their broad biocidal effect, the new preparations have the advantage that they are suitable for combating a very wide variety of both vegetable and animal pests.

They are not only efiicient herbicides but, when used in a concentration that does not produce any phytotoxic effects, they also display an outstanding activity against phytopathogenic organisms such as fungi, for example Altern aria solani, Phytophlhora infestans and Septoria apii, as well as against insects that harm plants, acarides, nematodes and their ova and larvae.

Furthermore, the new preparations may be used quite generally as microbicides, for example against Aspergillus species, and also against bacteria for example Staphylococcus aureus or Escherichia coli and quite generally as insecticides, for example against midges and flies. They also display a molluscicidal action.

In the manufacture of solutions of the compounds of the general Formula I that are ready for spraying there may be used, for example, petroleum fractions of a medium to high boiling range for example diesel oil or kerosene, coal tar oil and oils of vegetable or animal origin, as well as hydrocarbons for example alkylated naphthalenes, or tetrahydronaphthalene, if desired with the use of xylene mixtures, cyclohexanols, ketones, also chlorinated hydrocarbons for example trichloroethane and tetrachloroethane, trichloroethylene or triand tetrachlorobenzenes. It is advantageous to use organic solvents that boil above C.

Aqueous forms of application are preferably prepared 'by adding water to emulsion concentrates, pastes or wettable spray powders. Suitable emulsifiers or dispersants are nonionic products, for example condensation products of ethylene oxide with aliphatic alcohols, amines or carboxylic acids containing a long-chain hydrocarbon radical of about 10 to 20 carbon atoms, for example the condensation product of octadecyl alcohol with 25 to 30 mols of ethylene oxide, or of soybean fatty acid with 30 mols of ethylene oxide, or of commercial oleylamine with 15 mols of ethylene oxide, or of d'odecylmercaptan with 12 mols of ethylene oxide. As suitable anionic emulsifiers there may be mentioned the sodium salt of dodecyl alcohol sulfuric acid ester, the sodium salt of dodecyl benzenesulfonic acid, the potassium or triethanolamine salt of oleic acid or of abietic acid or of mixtures of these two acids, or the sodium salt of a petroleumsulfonic acid. Suitable cationic dispersants are quaternary ammonium compounds, for example cetyl pyridinium bromide or dihydroxyethyl benzyl dodecyl ammonium chloride.

Solid vehicles suitable for the manufacture of dusting or casting preparations are talcum, kaolin, bentonite, calcium carbonate, calcium phosphate, or coal, cork meal,

by themselves or in conjunction or admixture with conventional pesticides, especially insecticides, acaricides, nematocides, bactericides or further fungicides or herbicides respectively.

Particularly suitable for combating harmful insects and their ova as well as acarides are those new preparations which contain as active substance a com ound of the formula I N Q or the formula or of the formula fD- Q Particularly potent total or selective herbicides are those new preparations which contain as active substance one of the following compounds:

and

Especially suitably for combating harmful microorganisms, particularly phytopathogenic micro-organisms, are those new preparations which contain as active substance one of the following compounds The compounds of the general Formula I may be manufactured by known methods, for example by heatand ing bromopyridine with a phenol in the presence of an acid acceptor, or by heating N-pyridyl-(4)-pyridinium halides with a phenol. The salts of the compounds used in the present invention can be obtained in a simple manner by reaction with acids that are known to be capable of forming salts, for example with hydrochloric, sulfuric, nitric or perchloric acid. The N-oxides of the compounds used in this invention are likewise accessible by known methods by reaction with a suitable oxidant, for example hydrogen peroxide in an acetic acid solution.

The present invention further includes the new compounds of the following general formulae:

Hake

EXAMPLE 1 (a) 2-(meta-N,N-dimethylamino-phenoxy)-pyridine A mixture of 45 grams of meta-N,N-dimethylaminophenol, 44.5 grams of 2-bromopyridine and 42 grams of potassium carbonate was heated to 210 C., while being stirred. After 3 hours, the reaction mixture was poured into water, rendered strongly alkaline by adding a 10 N-sodium hydroxide solution in order to dissolve the excess phenol and then extracted with ether. The ethereal solution was dried with sodium sulfate and evaporated. From the resulting residue, 41.2 grams of the product distilled out; it boiled at 126 to 129 C. under a pressure of 0.04 mm. Hg and melted at 45 C.

The following compounds can be manufactured in a similar manner:

TABLE I Substance M.P., C.

pyn me. 8-.. 2-(4-chloro-3-methylphenoxy) pyridine- 121/0. 04--. 9.--" 2-(4-bromo-3-methylphenoxy) pyridine. 108/0. 09 10 2-(4-bromo-2-methylphenoLy) pyridine. /11 12",. 2-(ortho-methylphenoxy)pyridine 139- 13. 2- (2,4-dichlorophenoxy) pyridine. 14 2- (3-4 dieh1orophenoxy) pyridine 16 2-(4-nitrophenoxy) pyridine.

2-(4-bromophenoxy) pyridine.

5 (b) 81.5 grams of 2,4-dichlorophenol and 96.3 grams of N-pyridyl-(4)-pyridinium chloride were heated at 160 C. until a clear melt had formed. This solution was poured into a /1 liter of sodium carbonate solution of 10% strength and was then extracted with ether. The ethereal solution was washed with 3x100 cc. of 2 N-sodium hydroxide solution and 3 times with water, dried over sodiurn sulfate and the ether was distilled off. The residue was distilled under a high vacuum, to yield 21.3 grams of a compound of the formula B.P. 109118/0.02 mm. Hg; M.P. 45-48.

In a similar manner the following compounds were manufactured:

TABLE II 11 OZN 0- M.P.131l33.

1s Q-m- N 13.1. tar-9570.05 mmJHg;

M.P. sews.

13.1. 103'109/0.3 mm. Hg.

B.P. 130-132/11 mm. Hg.

B.P. ION-10470.02 mm. Hg.

B.P. 102'/0.02 mm. Hg.

B.P. 124134/0.05 mm. Hg;

B.P. 10070.3 mm. Hg.

O M. P. 179'185'.

TAB LE II-Contlnued 86 moo-Q-o N EXAMPLE 2 poured into water.

EXAMPLE 3 (A) Herbicidal eifect In a greenhouse, earthenware pots were filled with earth and seeded with the following plants: Allium' cepa, Alopecurus pratensis, Poa pratensis, Dac'tylz's glomerata, Beta vulgaris, Calendula chrysantha, Linum usitatissimum, Brassica rapa, Daacus carota, Spinacia oleacea, Lacluca sativa, Medicago sativa, Soja max and Phaesolus vulgaris.

(a) The pre-emergence treatment was carried out 2 days after seeding with spray broths prepared as described in Example 2, which contained as active substances the compounds of Example 1, Table 'I, No. 6 and Example 1(b). The amount applied corresponded to 20 kilograms of active substance per hectare. Evaluation was carried out 20 days after the treatment.

(b) The post-emergence treatment of the plant types enumerated above was carried out as described under (a) but only 12 days after seeding, when the plants had developed their second leaf. The amount applied corresponded to kg. of active substance per hectare. Evaluation was carried out 16 days after the treatment.

The results obtained are shown in the following tables:

(a) Pre-emergence treatment Amount applied Compound N0. Compound of Plants tested in kg.lhectare 6 of Table I, Example 1(b) Example 1 10 10 20 10 10 20 8 10 20 3 10 20 9 10 20 9 7 20 3 10 20 10 9 20 O 9 20 7 10 20 10 7 20 10 10 80111 20 1 3 Phaseolus 20 O 2 (b) Post-emergence treatment Amount applied Compound N0. Compound of Plants tested in kg./hectare 6 of Table 1, Example 1(b) Example 1 Allium 10 10 10 Alopecurus 10 10 10 a 10 10 10 Dactylim 10 10 10 eta r 10 10 10 Calendul 1O 9 9 Linum 10 10 10 Brassica. 10 10 9 Dances" 10 1 8 Spinacia- 10 10 10 Lactuca 10 10 6 Medicago 10 10 1O S0ja 10 8 4 Phaseolus 10 6 7 Values of assessment: 0=No efieet, 10=P1ant completely destroyed.

A similarly good result was also obtained with compounds Nos. 2, 3, 4 and 8 of Table I of Example 1(a) and Nos. 15, 16, 17, 23 and 29 to 34 of Table II.

(B) Insecticidal effect 1) Ovicidal efiect.The compounds Nos. 1, 3, 8 and (C) Microbicidal efiect Compound No. 6 of Table I of Example 1 displayed a good microbicidal effect against phytopathogenic fungi;- for example at a concentration of 0.2% of active substance a eifect against Alternaria solani on tomatoes and a eifect against Erysiphe cichoriacearumon Cucumis pepo was achieved without the plants treated being appreciably damaged. A similarly gOOd result was also obtained with the compounds No. 3 of Table I and Nos. 16, 22, 29, 32 and 33 of Table II. Compound No. 19 of Table II of Example 1 also displayed a very good effect against Staphylococcus aureus and against Escherichia C01.

(D) The compounds of the general Formulae I to III can also be used as defoliating agents, especially for cotton.

What is claimed is:

1. A method for combating undesired plant growth which comprises applying to the area where the said effect is desired, a herbicidal amount of a member selected from the group consisting of (a) a compound of the formula X I Q \N YD in which X represents a member selected from the group consisting of a hydrogen atom, a chlorine atom, a bromine atom, a nitro group, a trifluoromethyl group, a lower alkyl radical and the radical wherein A and Ag each represents a member selected from the group consisting of a hydrogen atom and a lower alkyl radical, Y represents a member selected from the group consisting of a hydrogen atom and a chlorine atom, and n represents a member of at most 4,

(b) an N-oxide of a compound as defined in this claim under (a), and

(c) a salt of a compound as defined in this claim under (a) with a member selected from the group consisting of hydrochloric, sulfuric, nitric, and perchloric acid.

2. A method for combating undesired plant growth which comprises applying to the area where the said etfect is desired, a herbicidal amount of the compound of the formula 3. A method for combating undesired plant growth which comprises applying to the area where the said effeet is desired, a herbicidal amount of the compound of the formula 4. A method for combating undesired plant growth which comprises applying to the area where the said cffeet is desired, a herbicidal amount of the compound of the formula 5. A preparation for combating undesired plant growth which comprises as active principle an herbicidal amount of a member selected from the group consisting of (a) a compound of the formula Q QQ in which X represents a member selected from the group consisting of a hydrogen atom, a chlorine atom, a bromine atom, a nitro group, a trifluoromethyl group, a lower alkyl radical and the radical References Cited UNITED STATES PATENTS 2,501,209 3/1950 Craig 71-2.5 2,299,782 10/1942 Allen et al. 260-297 3,244,722 4/1966 Johnston et al. 7l-2.5 3,295,946 1/1967 DAmico 71-2.5

LEWIS GOTTS, Primary Examiner.

G. HOLLRAH, Assistant Examiner.

US. Cl. X.R. 

